The objective of an agricultural crop spraying machine is to effectively distribute an agro-chemical spray over the largest area of crop in the least amount of time. The conventional design for such a machine is a wheeled base unit, be it trailed or self-propelled, which carries a tank, pump, and controls. The conventional design supplies the agro-chemical to the distribution booms or boom pipes extending from either side of the wheeled base unit, perpendicular to the direction of travel. The boom pipes support nozzle assemblies and deliver fluid to the nozzle assemblies to deliver the agro-chemical spray. The primary role of the nozzle assemblies is to provide a sealed connection between the pipe work of the boom pipe and the spray tips to allow the agrochemical to be distributed. This setup is referred to as a wet boom configuration.
Nozzle assemblies are distributed at regular, uniform intervals along the spray boom pipe. Each nozzle assembly has a turret to which spray tips can be coupled to the nozzle assembly to regulate the spray pattern and flow rate. The nozzle assemblies also position the spray tips at the correct angle with respect to the direction of travel. Each nozzle assembly has a turret to which the spray tips are coupled to regulate spray pattern and flow rate.
The control of the agro-chemical or fluid to the nozzle assemblies can be regulated by large section valves. The section valves regulate which group of nozzle assemblies receives fluid when desired by a user. When fluid is sent to the nozzle assemblies, a large section valve (such as a diaphragm check valve) opens with a low pressure increase in the fluid, allowing fluid to exit the nozzle assemblies through the spray tips. The nozzle assemblies are currently designed so that fluid flow to an individual nozzle assembly is shut off if a large section valve upstream of that individual nozzle assembly is closed. However, once a large section valve is closed, fluid flow is closed to not only the first nozzle assembly downstream of the large section valve, but also to each and every other nozzle assembly that is also downstream of the closed section valve.